1.A.62.2.4TRIC family homologue of 213 aas and 7 TMSs; it's high resolution 3-d structure is known (PDB# 5H36).
TRIC channels are implicated in Ca2+ signaling and homeostasis. Kasuya et al. 2016 presented crystal
structures of two prokaryotic TRIC channels in the closed state and conducted structure-based functional analyses
of these channels. Each trimer subunit consists of seven TMSs with two inverted 3 TMS repeats (Silverio and Saier 2011).
The electrophysiological, biochemical and
biophysical analyses revealed that TRIC channels possess an
ion-conducting pore within each subunit,
and that trimer formation contributes to the stability of the protein.
The symmetrically related
TMS2 and TMS5 helices are kinked at conserved glycine clusters, and
these kinks are important for channel activity. The kinks in TMS2 and
TMS5 generate lateral
fenestrations at each subunit interface that are occupied by lipid
molecules (Kasuya et al. 2016).